From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Engine and gearbox modifications and subsequent performance testing for a vehicle.
| Identifier | ExFiles\Box 109\5\ scan0120 | |
| Date | 10th March 1939 | |
| 664 F Dodd Please note for log book & return Rm{William Robotham - Chief Engineer} re. WXA-1 - Sg.{Arthur F. Sidgreaves - MD} We have now carried out the following work to Sg{Arthur F. Sidgreaves - MD}'s car. ENGINE. One set of Aerolite Raised Crown Pistons (6:1) compression ratio fitted. One complete new cylinder block. Bentley type camshaft. New type exhaust system deleting front expansion box. GEAR BOX. Latest type 1st. motion shaft fitted and Ransome & Marles Schatz type ball races fitted to 1st and 3rd motion shaft. As we had to dismantle the gear box from the chassis to do the necessary work to the box, it was a simple matter to take the engine out of the frame. We did this, as it was much more convenient to fit the new camshaft etc. in this manner. After completing the work to the engine we put it on the test bed and I attach herewith a power curve we obtained from this engine compared with the average 'M' Series Bentley and the average Wraith. We have now completed the car and checking this on Ticknall Hill against a standard chassis loaded up to the same weight, we obtained the figures attached. Rm{William Robotham - Chief Engineer}/FD{Frank Dodd - Bodies} is at the present time taking performance tests against the figures he obtained as reported in Rm{William Robotham - Chief Engineer}/FD{Frank Dodd - Bodies}9/JH28.2.39. We also attach figures giving the bore wear of the cylinder block dismantled from this engine. The speedometer on the car when it came to us read 17997 miles. contd- | ||